Genus, Plant Genus

What is a plant genus?

The genus is the first part of a plant’s botanical name used to properly describe it.

The binomial system created by Linnaeus in the eighteenth century is the method used to name plants. This system consists of the genus and species names. It is also referred to as being part of the plant taxonomy, as there are more than two names to fully describe a particular plant.

However, for most people, the  plant genus and species are sufficient. An analogy frequently used to help describe the genus name of a plant is that it can be likened to a person’s surname.

So, for example, the Oriental poppy – which is a common name for the plant – has the botanical, binomial name of Papaver orientalis. Papaver is the genus and orientalis is the species.

The genus name helps to relate a plant to other plants which share similar characteristics.

So, the group of plants which are beans are in the genus Phaseolus. This shows that they have a common ancestry, as they “share a surname”.

The bean genus contains different species, which will have different names. So, in this instance we can see that runner beans are Phaseolus cocchineus, common beans are Phaseolus vulgaris and lima beans are Phaseolus lunatus.

The generic name or plant genus name is a singular, Latinized noun and should have a capital letter.

Some genus names are the same as the common name, Clematis, for example.
Where the generic and common names are the same – as in clematis, the common name may be capitalized or not, but the plant genus name should be.

The plural of genus is genera.

The Botanical Latin used for the naming of plants can put some people off, but it isn’t really that difficult to understand the basics.
Although I do wonder about some definitions – For example, What is a genus? “A genus is a taxonomic category containing related species” – the answer is not a great deal of help even though it’s correct!

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